SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '40adf2f3256634455361a335ef6ce9a240526543cbeae4ecd2032420d70a8e3d' 
  AND token = 'Bk5bGalZoFwxE1kinslCPV64q4nJxbNhAMQEBl5GUo4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}